OK, I think my Gtech is messed up, or I am one. I finally got to try it out with the nitrous and the numbers are way off. Heres the scoop:

Race track says:
15.56 @ 88 mph off nitrous
14.19 @ 98 mph on nitrous


Gtech says:
15.48 @92 mph off nitrous
15.18 @ 96 mph on nitrous

The Gtech runs were on different days (about 2 weeks apart) but same road.

How is it that my mph is only 2 off but I'm a full second slower????? The no nitrous times are almost identical, but the mph is off 4.

I thought these Gtechs were better then this. And these times are not screwy runs, I did 3 off nitrous and 2 on, theses are just the fastest times.

I definately plan on going back to the track to get some real numbers sometime soon. This just kinda bugs me because I want to know what I can do without driving 2 hours to the track and paying $$$.

Any ideas as to whos screwed up here, gtech, maxima, or driver? LOL

 

probly a combination.. the gtech reads about 3mph high on my 16 second car and i think it only gets worse the faster you go.

on the other hand, theres no accounting for being a full second off on that et.. i dont know wtf that is.

my gtech has NEVER given me a screwy number. EVER, after i figured out how to use it.

one time it told me i had 1 hp after i accidently input my car as weighing 3 lbs. lol. now i know that a 3 lb rc car with 1 hp can keep up with me, lol.

 

From my experience with my friends G-tech...they give you ball park figures...not exact....can be used to help your tunning....to see any gains...but again it will not give you a definant number figures. But also weather can play a part in your times too. I hope this helps a bit.

 

sometimes my gtech says 0-60 7.04 and sometimes 8 seconds!u want real results, go to the track, u want practice driving use the gtech b4 track

 

This is why G-Tech times are NOT valid for trying to claim or prove anything about your car.

If you run them side-by-side at the track they can get sorta close, but even small bumps in the road can throw a g-tech off on the street. They're just not accurate for 1/4 mile. They seem to be pretty accurate for 0-60, but the longer you run them, the higher the error.

Take g-tech times like a grain of salt. It's just a toy.

For 0-60, the best thing you can do is find a stretch of road and then run 3 times in each direction. That cancels out any slight incline of the road, and even headwind and tailwind. Doing that I got an average of 8.0s in one direction on my Accord, and an average of 7.4s in the other. Overall average was 0-60 in 7.7s, which is about what the car will do in reality. CarTest analysis with a chassis dyno says that's pretty realistic also.

The accelerometer function, which measures in G's, is useful for doing thrust analysis though. I can use it for real-world correlation to calculated values such as whats in the shift point sticky thread in this forum.

 

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it really does vary that much in real life, tho. ive run 8.00 and low 9s 0-60 on my gtech. differences being weather and how i launch. those two factors alone can make that big a difference easily, and i have an auto. a 5 speed has the potential to be even more inconsistent. so i wouldnt blame that on the gtech.

id go farther than that. of course im hardcore, but knowing what i did about the variations of the gtech, i usually went out to the same deserted flat road at 1 or 2 am and ran 20-30 times every time i went out. when i use a number from my gtech, i know damn sure its not a fluke.

and as far as blah blah gtech not accurate, ONE track visit would cost me as much as i paid for the gtech. which is about 2-3 weeks of groceries to me, being in the financial state i am, so HELL no.

 

Yeah I know it's just a toy basically, not too accurate. I jus thought it would be fun to get an idea of what I will run until I can go to the track and find out for real. I just think its odd how far off the nitrous runs where et wise but so close mph wise. Weird. Oh well.

 

i tried using my friends g tech again last week and my time dropped 3 sec to a 13.00 just from adding a vb mod.

same g tech gave my a 15.3 with intake and y pipe 6months earlier.

like some one said they are just toys, not that accurate

 

i swear, either there are a lot of DEFECTIVE gtechs out there or there a lot of very deserving 'i can mess up ANYTHING! award' contenders out there who just arent getting credit. who knows.

 

i dont know about you guys but the gtech i own has been tested at the track and is within .10 every time so i dont consider it a toy at all

you could be calibrating it wrong or the road not be perfectly flat there are veriations in that kind of stuff but if used properly is very accurate except for the MPH

 

ditto. and i cant even count the number of times ive heard people post slips saying 'oh the equipment was fubared wtf i am noob omfg wOOOeee!' so it doesnt matter where you get your times, excuses and suptid comments are bound to follow on some front or another.

 

Mine is dead on. Mine was never off by more that .07 at the track, and is very reliable on the street. The big difference you may be noticing is that your launch sucks on the street. You probably don't do a burnout before the run, and if you have even the slightest tire spin, it will cost you big time. My G-Tech was dead on even when I had a run at the track where I went up in smoke, and let off to regain traction, and get back into it. I ran a 14.89, and the timer was at 14.88. You are probably just not running as good as you were at the track. Bottle pressure, air temp, traction, were you using octane boost? Too many factors to say it is wrong vs. a bad day on the street.

 

I thought mine was good too. My no nitrous runs where very close. The nitrous runs where made a week or so later, so something could have happend to it, maybe it got banged up.

Heres the deal though, I have NEVER ran 15 second times on nitrous at the track. I had a 55 shot, half a bottle, 70 degrees weather and ran a 14.8. Now I'm running a 75 shot, in 75-80 degrees and ran a 15.1???? Hell, last summer I was running mid 14s in 90-100 degrees at the track. I will definatelly take it to the track and find out cause this just seems too far off to be trusted.

 

right here

 

lol

i sure as hell got some fubared results out of mine, sure, but i figured out they were all my fault and since then its never given me a wacky number. thats the bottom line with 90% if not more of the gtech or similar device owners ive talked to.

 

ive never done anything that didnt involve some stupid simple screw up

 

I have had very good luck with my g-tech. When run at the track it was within few hundredths from the track time but the mph was about 3-4mph off if I am not mistaken. On one pass it was about a tenth off but I was not able to get the g-tech completly level before I staged. I heard once you get in the 12.00's range they are no longer accurate and the numbers get all crazy.

Dave
02 Maxima SE
85 El Camino w/Turbo V6 swap